1. Field of the Invention
The present invention relates to detection systems. More specifically, the present invention relates to electromagnetic target detection systems such as radar, ladar, sonar and other such systems.
2. Description of the Related Art
Several techniques are currently employed to detect a target utilizing electromagnetic energy such as radar, ladar, sonar and other such systems. Radar involves the transmission of a radio wave pulse which, when reflected by a target provides a return pulse which is received and processed to effectuate target detection.
Unfortunately, a noise jammer may frustrate a radar system. A noise jammer is a source which transmits noise near the transmit frequency of the radar. This noise source impedes the ability of the radar system to detect the type of target or the range thereof. This is problematic inasmuch as it may cause a premature launch of a weapon outside of its range of operation. This forces the use of a smaller weapon launch zone and may lead to a loss of a first shot capability, obviously highly undesirable for military applications.
The current method of obtaining range, when radar range is denied, is based on a conjecture as to the target""s altitude. Unfortunately, the range obtained by this method is highly inaccurate as it is based on a supposition of the target""s altitude. If a target is several miles away at some unknown range, guessing a target""s altitude with any accuracy can be very difficult. At normal closing speeds there is very little time to obtain more accurate estimates and the erroneous estimates can put the aircrew in jeopardy. Further, there is no way for the aircrew to know if the initial conjectures were correct.
Hence, there is a need for a system or method for determining the range of a noise-jamming target.
The need is addressed by the system and method for ascertaining range of a noise-jamming target of the present invention. Generally, the system includes a receiver; a data processor coupled to the receiver; and software adapted for execution by the data processor for computing range to a target transmitter using first and second assumptions with respect to the output power level thereof and interpolating with respect to an effort term calculated with respect thereto.
The method includes the steps of: making assumptions with respect to an output power level of a transmitter located at the target; measuring a level of power received from the transmitter by a receiver at first and second distances relative to the transmitter; calculating an error term with respect to the assumptions; interpolating with respect to the error term to make a range calculation; and outputting the range calculation when the error term reaches a predetermined threshold.